Modulating valve



N ov. 271,'1951 s K TAYLOR 2,576,246

. MODULATING VALVE Filed Nov. 15. 1947 -'frMz/a K Dinox Patented Nov. 27, 1951 MODULATING vALvE Samuel K. Taylor, Cleveland Heights, Ohio Application November 15, 1947, Serial No. 786,267

(Cl. 23S-80) 9 Claims.

This invention relates to improvements in modulating valves for fluid fuel burners in space heaters. The system consists of a standard fuel valve with control appurtenances such that fluid fuel flow may be modulated by a potentiometer thermostat. By this means the rate of operation `of the burner is'increased or decreased in accordance with the change of temperature o the air in the space to be heated, providing a substantially continuous supply of heat as required rather than the off and on operation conventionally employed.

One of the objects of the invention is the provision of simple means for accomplishing the modulation of a fluid fuel burner.

Another object is the provision of modulating means by combining with a vconventional valve a movable stop the position of which is automatically controlled in accordance with the heat demand.

A further object is the provision of means for causing such a stop to -be withdrawn when the burner closes, in `order that when the fuel is again turned on there shall be full fiow to the burner to insure ignition from the pilot, the movement of the stop for limiting fuel flow taking place thereafter.

Other objects and features of novelty will appear as I proceed with the description of that embodiment of the invention which, for the purposes of the present application, I have illustrated in the accompanying drawing, in which the single figure is a diagrammatic illustration of apparatus and wiring embodying the invention as applied to a gas burner. I

In the drawing I represents a gas valve of the diaphragm type in which there is a diaphragm II carrying a valve piece I2 which cooperates with a valve seat I3. I4 is a pressure chamber above the diaphragm into which line pressure may be introduced by way of passages I5 and I6 and an intercommunicating valve chamber I1. Above the latter chamber a passage I8 leads to atmosphere. A double ended valve piece I9 in chamber I1 is adapted to close either the passage I5 or the passage I8. When the valve piece I9 is in the illustrated position, pressure builds up in chamber I4. AWhen the valve piece I9 is down to close olf passage I5 lthe passage I6. I1, I8 constitutes a bleed passage for reducing the pressure in chamber I4 to atmospheric and permitting the diaphragm vto rise and open the main valve I0. Valve piece I9 is arranged to be actuated upwardly-by a coil spring and downwardly bya `solenoid 2l the action of which is sufficiently powerful to overcome spring 20 and lower valve pieceI I9 to its seat at the top of passage I5. The armature 9 of the solenoid carries a, movable electric contact 22 which is adapted to engage a fixed contact 23 when the solenoid is energized.

25 is an elongated stop which is slidably disposed in an opening through the casing of valve I0 above the center of valve piece I2. At its upper end stop 25 is pivoted to a lever 2B which has its ffulcrum at 21 in a boss on the casing. Movement of the lever clockwise is limited by a pin 28 which is adjustably threaded into another boss on the casing.

A bracket 30 attached to the casing of valve I0 supports the lower end of almetal bellows 3l, the upper end of which carries a =Cshaped arm 32 which is attached to the upper endl of a second metal bellows 33 identical in form and size with bellows 3| and partially filled with the same kind of low boiling point fluid, ether for example. The lower end of bellows 33 is pivotally connected with the power end of lever 2B. An electric heating coil 35 is mounted above bellows 3| and a hood 36 encloses the coil and the major part of the bellows in order that the :fluid within the bellows may respond quickly to heat emanating from the coil. The double bellows arrangement illustrated compensates for changes in ambient temperature, as will be obvious to those skilled in the art.

At the right hand side of the drawing I have illustrated a potentiometer room thermostat indicated generally at 4I). It comprises a metal bellows 4I responsive to temperature changes and having an operating ram 42 which presses against the long arm of a bell crank lever 43 pivotally mounted at 44 on an insulation panel 45. Lever 44 is biased clockwise by a tension lspring 46, the tension of which may be varied more or less by a pin 41 mounted in an adjusting screw 48 which is threadably mounted in a bracket 49 attached to the panel 45. By turning screw 48, pin 41 is caused to travel up or down in the convolutions of the spring, thereby varying the force of the spring.

Bracket 49 also carries a cylinder 50 of insulation material upon which is wound a coil of resistance wire 5I. The upper end of bell crank 43 runs over coil 5I as the pressure in bellows 4| changes. Bell crank lever 43 carries a block 52 of insulation upon which are mounted two spring fingers 53 and 54 which carry electric contacts 55 and 56. Finger 53 tends to swing toward the right to bring these contacts into- Vwith more or less resistance from coil I.t mostcases this resistance Willbe low., so that coil engagement, but as illustrated in the drawing it is exed out of contacting position by the action of a permanent magnet 5'I.

60 and 6I represent line Wires. From line Wire 60 a conductor 62 leads to heating coil 35, and from that coil Ya conductor 63 leads to contact 22. From contact 23 aV conductor 64 leads to bell crank lever 43 and from one end of resistance coil 5I conductors 65 and 66 lead to line wire 6I..

From conductor-'62a further conductorlfextends to Vsolenoid 2|, while a conductor 68 runs from the opposite end of the solenoid to spring finger 53.

Spring linger 54 and its contact 56Y are connected by .a conductor 69 with conductor..

66 and line wire 6I.

Operation-The parts are showninthe burner off condition with the circuit through solenoid` 2| broken at the contacts 55, 56, and thevalve piece I9 raised by the coil spring `2l). Linepres= sure of gas is therefore: present in chamber I4,

which; holds `the diaphragm-down in-valve'-closing` position.. Pit-this time also the-'circuit-through heatingcoil. lisV broken. at--thevcontacts 22; 23,'

so.. thatlthey operating bellows3I-1--is-cool and` therefore.V contracted. C-shaped arm3v2 is thus lowered and .lex/er. 2521's. disposed vas shown,V with stop..25.raised, .I

.Now wherrthe.:temperatureninthe. roomin 46fto. swing. bellhcranll clockwise.

53:.'Will sWingover to theright,.causinggcontact 55 topenga-ge Contact 5.5. This will closeathe,v circuit through solenoid 2I, ,which .will then Y operateto lower valve piece I f-closin'gof the passage I 5-and opening the bleed passage. |6.,. II, I8;

Pressure in chamber Illawill. .thereby; be .relieved and the valve will open fully,

soon as solenoidli is energized armatureil` will be pulled downrand the contact 22 will be caused to engage fixed Contact 23.` The circuit.

through heating coil-35 rwilltljren be established. In

35'willthrow offY heat rapidly, expanding bellowsA 3.I and depressing stop25 tothe limit permitted by-pin 25.v If thelimited flow of'gas Visrnotsufcient to raise the. room temperature to 'thedesiredpoint and` maintain it there, bell. crank lever 43 will swing clockwise further, introducing more resistanceinto theheater circuit, whereupon the 'lever 26 will swing. counter clockwise and stop 25.wil .rise permitting. the gas pressure in the-line to'liftthe diaphragm and openther mainyalve to a..greater;extent.

A limited gas flow is thereby maintained and t the-.burner operates continuously over considerable periods of time with variations in gas ow taking place to maintain. room temperature with a minimum `degree of variation.V As roomptenl Y bell crank IeVerrsSzv/ilIsWing counterclockwise farenough to permit magnet 57. `to attractV finger 53, breaking the circuit through solenoid 2l .and closingthemainyalver It will be` observed-therefore thatth'e vcontrols inthelfsystemprovide an'v off .and on.;foperation of' thev main'valve 1v1-ith the onj position 'regu-l lated by.: themovements of stop; .f25lfto modulate the flow. The system has all of the Vsafety features of one employing a conventional diaphragm valve. In case of-power failure the valve closes immediately. On the rst call for heat the valve opens fully, providing good Y ignition from the pilot. The adjustable limit pin 28 puts a low limit on the valve opening such as will support combustion in the burner.

While I have illustrated the systemras applied to a: diaphragm type of valve, it willbe appreciated thatth'e invention' is not so' limited, as a diierent type of valve could be substituted.

VHaving-thus described my invention, I claim: 1.v In` combination, a uid valve comprising a valve seat and a valve piece adapted to assume rclosed"position and a series of different open ,positions-providing modulated fluid flow, a room thermostat, means responsive thereto for causing sai'd"valve' piece to move toward or away from said seat, a movable stop in the path of movementiofv said valve piece, and. means.A responsive to said-l room l thermostat ferr-.moving said. stop.-A progressively toward-hsaid.. seat-in. proportion to v the rise: lin room temperature...

2.. Incom-bination, .afuid valve: comprising.;a'` Valve seat and .a .valve piece.. adapted to assume l closed. `position and iaseries of different open vpositions.. providing modulated iiuid.- llovxhfaV room thermostat; meansresponsive thereto for causing? said valveszpiece tomovetovuard or away from saic'bseatza movable Ystop 'in the 'pathof.move-g Y ment of said valve piece,.. an: electric heater,

means. responsive to a. gradual.. unidirectional .change iizrheat `emitted-by said heater formov-. ing said stop progressively.towardsaidk seat, and

potentiometer meansalso responsivel to saidroom thermostat. forV controlling the ow'of current through said` heater.

3; In :.combinationf,- afluid, valve,Y conflprising'l a valve seat and a valve piece adapted to `assume closedposition and aseriesfof diierentopen positions providing. modulated fluid ow., a room thermostat; means responsive thereto forcausing said valveA piece to movel toward or away from said heater. circuit, said means for causingthe operation, of'said valve piece functioning simultaneously with the closingofY the valve1to'open said switch.

4; In combination, a fluid valve comprising.-aV valve seat-.and a valve piece,V said valvevpiece f being adapted-to .assume :fullyclosed `position and a series of openpositions of dierent degrees providingv modulatedl'ow, oitV and on means for.'` openingf-andclosingsaid valve, a room thermostat` controlling said oli vand on means, a stop movable lingrfsaid'stop advancing means, saidstopA iny any offts'advanced pcsitionsbeingadaptedto limitv the :opening movement of Vsaid valve piece.

5. In combination; aruid valve comprising `a1 valve-seat'a-nd ai valvev piece; said valve piece. bei-ng. adapted to `assume fully-closed positionV and a.series lof open positions of" different degrees;

.-1 providing-V .modulated,-.ew,fio1 and; @means-'for opening and closing said valve, a room thermostat controlling said ofi and on means, a stop movable in the path of said valve piece and biased away from said valve seat, means for advancing said stop toward said valve seat, potentiometer means actuated by said thermostat for controlling said stop advancing means, said stop in any of its advanced positions being adapted to limit the opening movement of said valve piece, and means acting simultaneously with the closing of said valve for disabling said stop advancing means.

6. In combination, a diaphragm gas valve having a control chamber above the diaphragm and a valve seat therebelow, said valve having a bypass from the intake side of the valve to the control chamber and a bleed passage from said chamber, solenoid valve means for opening or closing said bleed passage, a movable stop projecting into said chamber terminating concentric with said diaphragm and biased away from the diaphragm, means for advancing said stop toward said seat, said last named means being adapted to overpower gas pressure on the lower side of said diaphragm when said bleed passage is open, a room thermostat, means responsive thereto for operating said soleond valve and a potentiometer also responsive to said room` thermostat for controlling the action of said stop advancing means.

7. In combination, a diaphragm gas valve having a control chamber above the diaphragm and a valve seat therebelow, said valve having a bypass from the intake side of the valve to the control chamber and a. bleed passage fromY said chamber, solenoid valve means for opening or closing said bleed passage, a movable stop projecting into said chamber terminating concentric with said diaphragm and biased away from the diaphragm, means for advancing said stop toward said seat, said last named means being adapted to overpower gas pressure on thel lower side of said diaphragm when said bleed passage is open, a room thermostat, means Vresponsive thereto for operating said solenoid valve, a potentiometer also responsive to said room thermostat for controlling the action of said stop advancing means. and means for disabling said stop advancing means, said disabling means lacting upon the movement of said solenoid valve to close said bleed passage.

8. In combination, a diaphragm gas valve having a control chamber above the diaphragm and a valve seat therebelow, said valve having a bypass from the intake side of the valve to the control chamber and a bleed passage from said chamber, solenoid valve means for opening or closing said bleed passage, a movable stop projecting into said chamber terminating concentric with said diaphragm and biased away from the diaphragm, an electric heater, means responsive to a gradual unidirectional change in heat emitted by said heater for moving said stop means progressively toward said seat, said last named means being adapted to overpower gas pressure on the lower side of said diaphragm when said bleed passage is open, a room thermostat, means responsive thereto for operating said solenoid valve and a potentiometer also responsive to said room thermostat for controlling current through said heater.

9. In combination, a Huid valve comprising a valve seat and a valve piece adapted to assume closed position and a series of different open positions providing modulated fluid flow', a room thermostat, means responsive thereto for causing said valve piece to move either to fully open or fully closed position, a movable stop' in the path of movement of said valve piece, and means responsive to said room thermostat after the said valve piece moves to open position for moving said stop progressively toward said seat in proportion to the rise in room temperature.

SAMUEL K. TAYLOR.

REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATENTS Number Name Date 1,126,248 Mauck et al. Jan. 26, 1915 1,713,707 McKee Mat7 21, 1929 2,262,823 Stearns Nov. 18, 1941 2,285,913 Derrah June 9, 1942 2,329,829 Breese Sept. 21, 1943 2,470,572 Miller et al May 17, 1949 2,529,378 Dube et al Nov. 7, 1950 

